I painstakingly used video transcription searches to figure out where I heard this from and I finally found it!
It was touched on in this video Something’s Hiding Outside This Game… at 52 minutes.
The actual work being talked about is Three Versions of Judas by Jorge Luis Borges.
As a pansexual I feel that Bi and Pan have enough differences to both be justified while the others are micro labels (not invalid, just less useful as labels).
But I recognize I’m drawing that line very conveniently for myself.